The present invention relates to decorative ribbon or sheet material.
The three primary types of decorative ribbon in widespread use today are woven yarn-based ribbons, nonwoven yarn-based ribbons, and foamed-oriented polypropylene-based ribbons.
The yarn-based ribbons are generally the finest in quality in terms of yarn-like luster, texture, feel, quality of color, and other often subjective qualities. Unfortunately, such ribbons are relatively expensive to manufacture. The polypropylene-based ribbons while being of lesser cost do not generally offer aesthetics equivalent to that of yarn-based ribbons.
While the aesthetics of a decorative ribbon are often a subjective matter, the aesthetics can be described to a certain extent through a description of the reflective properties of the ribbon.
Diffuse reflection scatters the light in all directions with no one direction having significantly more light reflected towards it than another direction. A piece of paper is an example of a diffuse reflector.
Specular reflection is the type which is obtained off of a smooth mirror-like surface. When light strikes its surface it is reflected to an equal, but opposite angle from that of the incident beam. Light is returned to the source only when the light beam is exactly perpendicular to the surface.
Retro or reflex reflecting materials return incoming light directly to the source. This type of material is commonly used in traffic signs and license plates.
Decorative ribbons preferably exhibit little or no retroreflection. Furthermore, such ribbons preferably exhibit a certain balance of diffuse and specular reflection.
Yarn-based ribbons generally exhibit little retroreflection and exhibit a desirable balancing of diffuse and specular reflection. On the other hand, foamed-oriented polypropylene-based ribbons generally exhibit a greater amount of specular reflection and a lesser amount of diffuse reflection than the yarn-based ribbons.
Furthermore, the colors of foamed-oriented polypropylene ribbon are often diminished because of the foaming process used for producing their cellular structure. The resultant colors, especially the darker colors, often have a washed-out colored appearance.